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Diffstat (limited to 'drivers/parport/ieee1284.c')
| -rw-r--r-- | drivers/parport/ieee1284.c | 789 |
1 files changed, 789 insertions, 0 deletions
diff --git a/drivers/parport/ieee1284.c b/drivers/parport/ieee1284.c new file mode 100644 index 000000000..4547ac44c --- /dev/null +++ b/drivers/parport/ieee1284.c @@ -0,0 +1,789 @@ +/* + * IEEE-1284 implementation for parport. + * + * Authors: Phil Blundell <philb@gnu.org> + * Carsten Gross <carsten@sol.wohnheim.uni-ulm.de> + * Jose Renau <renau@acm.org> + * Tim Waugh <tim@cyberelk.demon.co.uk> (largely rewritten) + * + * This file is responsible for IEEE 1284 negotiation, and for handing + * read/write requests to low-level drivers. + * + * Any part of this program may be used in documents licensed under + * the GNU Free Documentation License, Version 1.1 or any later version + * published by the Free Software Foundation. + * + * Various hacks, Fred Barnes <frmb2@ukc.ac.uk>, 04/2000 + */ + +#include <linux/module.h> +#include <linux/threads.h> +#include <linux/parport.h> +#include <linux/delay.h> +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/timer.h> +#include <linux/sched/signal.h> + +#undef DEBUG /* undef me for production */ + +#ifdef CONFIG_LP_CONSOLE +#undef DEBUG /* Don't want a garbled console */ +#endif + +/* Make parport_wait_peripheral wake up. + * It will be useful to call this from an interrupt handler. */ +static void parport_ieee1284_wakeup (struct parport *port) +{ + up (&port->physport->ieee1284.irq); +} + +static void timeout_waiting_on_port (struct timer_list *t) +{ + struct parport *port = from_timer(port, t, timer); + + parport_ieee1284_wakeup (port); +} + +/** + * parport_wait_event - wait for an event on a parallel port + * @port: port to wait on + * @timeout: time to wait (in jiffies) + * + * This function waits for up to @timeout jiffies for an + * interrupt to occur on a parallel port. If the port timeout is + * set to zero, it returns immediately. + * + * If an interrupt occurs before the timeout period elapses, this + * function returns zero immediately. If it times out, it returns + * one. An error code less than zero indicates an error (most + * likely a pending signal), and the calling code should finish + * what it's doing as soon as it can. + */ + +int parport_wait_event (struct parport *port, signed long timeout) +{ + int ret; + + if (!port->physport->cad->timeout) + /* Zero timeout is special, and we can't down() the + semaphore. */ + return 1; + + timer_setup(&port->timer, timeout_waiting_on_port, 0); + mod_timer(&port->timer, jiffies + timeout); + ret = down_interruptible (&port->physport->ieee1284.irq); + if (!del_timer_sync(&port->timer) && !ret) + /* Timed out. */ + ret = 1; + + return ret; +} + +/** + * parport_poll_peripheral - poll status lines + * @port: port to watch + * @mask: status lines to watch + * @result: desired values of chosen status lines + * @usec: timeout + * + * This function busy-waits until the masked status lines have + * the desired values, or until the timeout period elapses. The + * @mask and @result parameters are bitmasks, with the bits + * defined by the constants in parport.h: %PARPORT_STATUS_BUSY, + * and so on. + * + * This function does not call schedule(); instead it busy-waits + * using udelay(). It currently has a resolution of 5usec. + * + * If the status lines take on the desired values before the + * timeout period elapses, parport_poll_peripheral() returns zero + * immediately. A return value greater than zero indicates + * a timeout. An error code (less than zero) indicates an error, + * most likely a signal that arrived, and the caller should + * finish what it is doing as soon as possible. +*/ + +int parport_poll_peripheral(struct parport *port, + unsigned char mask, + unsigned char result, + int usec) +{ + /* Zero return code is success, >0 is timeout. */ + int count = usec / 5 + 2; + int i; + unsigned char status; + for (i = 0; i < count; i++) { + status = parport_read_status (port); + if ((status & mask) == result) + return 0; + if (signal_pending (current)) + return -EINTR; + if (need_resched()) + break; + if (i >= 2) + udelay (5); + } + + return 1; +} + +/** + * parport_wait_peripheral - wait for status lines to change in 35ms + * @port: port to watch + * @mask: status lines to watch + * @result: desired values of chosen status lines + * + * This function waits until the masked status lines have the + * desired values, or until 35ms have elapsed (see IEEE 1284-1994 + * page 24 to 25 for why this value in particular is hardcoded). + * The @mask and @result parameters are bitmasks, with the bits + * defined by the constants in parport.h: %PARPORT_STATUS_BUSY, + * and so on. + * + * The port is polled quickly to start off with, in anticipation + * of a fast response from the peripheral. This fast polling + * time is configurable (using /proc), and defaults to 500usec. + * If the timeout for this port (see parport_set_timeout()) is + * zero, the fast polling time is 35ms, and this function does + * not call schedule(). + * + * If the timeout for this port is non-zero, after the fast + * polling fails it uses parport_wait_event() to wait for up to + * 10ms, waking up if an interrupt occurs. + */ + +int parport_wait_peripheral(struct parport *port, + unsigned char mask, + unsigned char result) +{ + int ret; + int usec; + unsigned long deadline; + unsigned char status; + + usec = port->physport->spintime; /* usecs of fast polling */ + if (!port->physport->cad->timeout) + /* A zero timeout is "special": busy wait for the + entire 35ms. */ + usec = 35000; + + /* Fast polling. + * + * This should be adjustable. + * How about making a note (in the device structure) of how long + * it takes, so we know for next time? + */ + ret = parport_poll_peripheral (port, mask, result, usec); + if (ret != 1) + return ret; + + if (!port->physport->cad->timeout) + /* We may be in an interrupt handler, so we can't poll + * slowly anyway. */ + return 1; + + /* 40ms of slow polling. */ + deadline = jiffies + msecs_to_jiffies(40); + while (time_before (jiffies, deadline)) { + if (signal_pending (current)) + return -EINTR; + + /* Wait for 10ms (or until an interrupt occurs if + * the handler is set) */ + if ((ret = parport_wait_event (port, msecs_to_jiffies(10))) < 0) + return ret; + + status = parport_read_status (port); + if ((status & mask) == result) + return 0; + + if (!ret) { + /* parport_wait_event didn't time out, but the + * peripheral wasn't actually ready either. + * Wait for another 10ms. */ + schedule_timeout_interruptible(msecs_to_jiffies(10)); + } + } + + return 1; +} + +#ifdef CONFIG_PARPORT_1284 +/* Terminate a negotiated mode. */ +static void parport_ieee1284_terminate (struct parport *port) +{ + int r; + port = port->physport; + + /* EPP terminates differently. */ + switch (port->ieee1284.mode) { + case IEEE1284_MODE_EPP: + case IEEE1284_MODE_EPPSL: + case IEEE1284_MODE_EPPSWE: + /* Terminate from EPP mode. */ + + /* Event 68: Set nInit low */ + parport_frob_control (port, PARPORT_CONTROL_INIT, 0); + udelay (50); + + /* Event 69: Set nInit high, nSelectIn low */ + parport_frob_control (port, + PARPORT_CONTROL_SELECT + | PARPORT_CONTROL_INIT, + PARPORT_CONTROL_SELECT + | PARPORT_CONTROL_INIT); + break; + + case IEEE1284_MODE_ECP: + case IEEE1284_MODE_ECPRLE: + case IEEE1284_MODE_ECPSWE: + /* In ECP we can only terminate from fwd idle phase. */ + if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE) { + /* Event 47: Set nInit high */ + parport_frob_control (port, + PARPORT_CONTROL_INIT + | PARPORT_CONTROL_AUTOFD, + PARPORT_CONTROL_INIT + | PARPORT_CONTROL_AUTOFD); + + /* Event 49: PError goes high */ + r = parport_wait_peripheral (port, + PARPORT_STATUS_PAPEROUT, + PARPORT_STATUS_PAPEROUT); + if (r) + pr_debug("%s: Timeout at event 49\n", + port->name); + + parport_data_forward (port); + pr_debug("%s: ECP direction: forward\n", port->name); + port->ieee1284.phase = IEEE1284_PH_FWD_IDLE; + } + + fallthrough; + + default: + /* Terminate from all other modes. */ + + /* Event 22: Set nSelectIn low, nAutoFd high */ + parport_frob_control (port, + PARPORT_CONTROL_SELECT + | PARPORT_CONTROL_AUTOFD, + PARPORT_CONTROL_SELECT); + + /* Event 24: nAck goes low */ + r = parport_wait_peripheral (port, PARPORT_STATUS_ACK, 0); + if (r) + pr_debug("%s: Timeout at event 24\n", port->name); + + /* Event 25: Set nAutoFd low */ + parport_frob_control (port, + PARPORT_CONTROL_AUTOFD, + PARPORT_CONTROL_AUTOFD); + + /* Event 27: nAck goes high */ + r = parport_wait_peripheral (port, + PARPORT_STATUS_ACK, + PARPORT_STATUS_ACK); + if (r) + pr_debug("%s: Timeout at event 27\n", port->name); + + /* Event 29: Set nAutoFd high */ + parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0); + } + + port->ieee1284.mode = IEEE1284_MODE_COMPAT; + port->ieee1284.phase = IEEE1284_PH_FWD_IDLE; + + pr_debug("%s: In compatibility (forward idle) mode\n", port->name); +} +#endif /* IEEE1284 support */ + +/** + * parport_negotiate - negotiate an IEEE 1284 mode + * @port: port to use + * @mode: mode to negotiate to + * + * Use this to negotiate to a particular IEEE 1284 transfer mode. + * The @mode parameter should be one of the constants in + * parport.h starting %IEEE1284_MODE_xxx. + * + * The return value is 0 if the peripheral has accepted the + * negotiation to the mode specified, -1 if the peripheral is not + * IEEE 1284 compliant (or not present), or 1 if the peripheral + * has rejected the negotiation. + */ + +int parport_negotiate (struct parport *port, int mode) +{ +#ifndef CONFIG_PARPORT_1284 + if (mode == IEEE1284_MODE_COMPAT) + return 0; + pr_err("parport: IEEE1284 not supported in this kernel\n"); + return -1; +#else + int m = mode & ~IEEE1284_ADDR; + int r; + unsigned char xflag; + + port = port->physport; + + /* Is there anything to do? */ + if (port->ieee1284.mode == mode) + return 0; + + /* Is the difference just an address-or-not bit? */ + if ((port->ieee1284.mode & ~IEEE1284_ADDR) == (mode & ~IEEE1284_ADDR)){ + port->ieee1284.mode = mode; + return 0; + } + + /* Go to compatibility forward idle mode */ + if (port->ieee1284.mode != IEEE1284_MODE_COMPAT) + parport_ieee1284_terminate (port); + + if (mode == IEEE1284_MODE_COMPAT) + /* Compatibility mode: no negotiation. */ + return 0; + + switch (mode) { + case IEEE1284_MODE_ECPSWE: + m = IEEE1284_MODE_ECP; + break; + case IEEE1284_MODE_EPPSL: + case IEEE1284_MODE_EPPSWE: + m = IEEE1284_MODE_EPP; + break; + case IEEE1284_MODE_BECP: + return -ENOSYS; /* FIXME (implement BECP) */ + } + + if (mode & IEEE1284_EXT_LINK) + m = 1<<7; /* request extensibility link */ + + port->ieee1284.phase = IEEE1284_PH_NEGOTIATION; + + /* Start off with nStrobe and nAutoFd high, and nSelectIn low */ + parport_frob_control (port, + PARPORT_CONTROL_STROBE + | PARPORT_CONTROL_AUTOFD + | PARPORT_CONTROL_SELECT, + PARPORT_CONTROL_SELECT); + udelay(1); + + /* Event 0: Set data */ + parport_data_forward (port); + parport_write_data (port, m); + udelay (400); /* Shouldn't need to wait this long. */ + + /* Event 1: Set nSelectIn high, nAutoFd low */ + parport_frob_control (port, + PARPORT_CONTROL_SELECT + | PARPORT_CONTROL_AUTOFD, + PARPORT_CONTROL_AUTOFD); + + /* Event 2: PError, Select, nFault go high, nAck goes low */ + if (parport_wait_peripheral (port, + PARPORT_STATUS_ERROR + | PARPORT_STATUS_SELECT + | PARPORT_STATUS_PAPEROUT + | PARPORT_STATUS_ACK, + PARPORT_STATUS_ERROR + | PARPORT_STATUS_SELECT + | PARPORT_STATUS_PAPEROUT)) { + /* Timeout */ + parport_frob_control (port, + PARPORT_CONTROL_SELECT + | PARPORT_CONTROL_AUTOFD, + PARPORT_CONTROL_SELECT); + pr_debug("%s: Peripheral not IEEE1284 compliant (0x%02X)\n", + port->name, parport_read_status (port)); + port->ieee1284.phase = IEEE1284_PH_FWD_IDLE; + return -1; /* Not IEEE1284 compliant */ + } + + /* Event 3: Set nStrobe low */ + parport_frob_control (port, + PARPORT_CONTROL_STROBE, + PARPORT_CONTROL_STROBE); + + /* Event 4: Set nStrobe and nAutoFd high */ + udelay (5); + parport_frob_control (port, + PARPORT_CONTROL_STROBE + | PARPORT_CONTROL_AUTOFD, + 0); + + /* Event 6: nAck goes high */ + if (parport_wait_peripheral (port, + PARPORT_STATUS_ACK, + PARPORT_STATUS_ACK)) { + /* This shouldn't really happen with a compliant device. */ + pr_debug("%s: Mode 0x%02x not supported? (0x%02x)\n", + port->name, mode, port->ops->read_status (port)); + parport_ieee1284_terminate (port); + return 1; + } + + xflag = parport_read_status (port) & PARPORT_STATUS_SELECT; + + /* xflag should be high for all modes other than nibble (0). */ + if (mode && !xflag) { + /* Mode not supported. */ + pr_debug("%s: Mode 0x%02x rejected by peripheral\n", + port->name, mode); + parport_ieee1284_terminate (port); + return 1; + } + + /* More to do if we've requested extensibility link. */ + if (mode & IEEE1284_EXT_LINK) { + m = mode & 0x7f; + udelay (1); + parport_write_data (port, m); + udelay (1); + + /* Event 51: Set nStrobe low */ + parport_frob_control (port, + PARPORT_CONTROL_STROBE, + PARPORT_CONTROL_STROBE); + + /* Event 52: nAck goes low */ + if (parport_wait_peripheral (port, PARPORT_STATUS_ACK, 0)) { + /* This peripheral is _very_ slow. */ + pr_debug("%s: Event 52 didn't happen\n", port->name); + parport_ieee1284_terminate (port); + return 1; + } + + /* Event 53: Set nStrobe high */ + parport_frob_control (port, + PARPORT_CONTROL_STROBE, + 0); + + /* Event 55: nAck goes high */ + if (parport_wait_peripheral (port, + PARPORT_STATUS_ACK, + PARPORT_STATUS_ACK)) { + /* This shouldn't really happen with a compliant + * device. */ + pr_debug("%s: Mode 0x%02x not supported? (0x%02x)\n", + port->name, mode, + port->ops->read_status(port)); + parport_ieee1284_terminate (port); + return 1; + } + + /* Event 54: Peripheral sets XFlag to reflect support */ + xflag = parport_read_status (port) & PARPORT_STATUS_SELECT; + + /* xflag should be high. */ + if (!xflag) { + /* Extended mode not supported. */ + pr_debug("%s: Extended mode 0x%02x not supported\n", + port->name, mode); + parport_ieee1284_terminate (port); + return 1; + } + + /* Any further setup is left to the caller. */ + } + + /* Mode is supported */ + pr_debug("%s: In mode 0x%02x\n", port->name, mode); + port->ieee1284.mode = mode; + + /* But ECP is special */ + if (!(mode & IEEE1284_EXT_LINK) && (m & IEEE1284_MODE_ECP)) { + port->ieee1284.phase = IEEE1284_PH_ECP_SETUP; + + /* Event 30: Set nAutoFd low */ + parport_frob_control (port, + PARPORT_CONTROL_AUTOFD, + PARPORT_CONTROL_AUTOFD); + + /* Event 31: PError goes high. */ + r = parport_wait_peripheral (port, + PARPORT_STATUS_PAPEROUT, + PARPORT_STATUS_PAPEROUT); + if (r) { + pr_debug("%s: Timeout at event 31\n", port->name); + } + + port->ieee1284.phase = IEEE1284_PH_FWD_IDLE; + pr_debug("%s: ECP direction: forward\n", port->name); + } else switch (mode) { + case IEEE1284_MODE_NIBBLE: + case IEEE1284_MODE_BYTE: + port->ieee1284.phase = IEEE1284_PH_REV_IDLE; + break; + default: + port->ieee1284.phase = IEEE1284_PH_FWD_IDLE; + } + + + return 0; +#endif /* IEEE1284 support */ +} + +/* Acknowledge that the peripheral has data available. + * Events 18-20, in order to get from Reverse Idle phase + * to Host Busy Data Available. + * This will most likely be called from an interrupt. + * Returns zero if data was available. + */ +#ifdef CONFIG_PARPORT_1284 +static int parport_ieee1284_ack_data_avail (struct parport *port) +{ + if (parport_read_status (port) & PARPORT_STATUS_ERROR) + /* Event 18 didn't happen. */ + return -1; + + /* Event 20: nAutoFd goes high. */ + port->ops->frob_control (port, PARPORT_CONTROL_AUTOFD, 0); + port->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL; + return 0; +} +#endif /* IEEE1284 support */ + +/* Handle an interrupt. */ +void parport_ieee1284_interrupt (void *handle) +{ + struct parport *port = handle; + parport_ieee1284_wakeup (port); + +#ifdef CONFIG_PARPORT_1284 + if (port->ieee1284.phase == IEEE1284_PH_REV_IDLE) { + /* An interrupt in this phase means that data + * is now available. */ + pr_debug("%s: Data available\n", port->name); + parport_ieee1284_ack_data_avail (port); + } +#endif /* IEEE1284 support */ +} + +/** + * parport_write - write a block of data to a parallel port + * @port: port to write to + * @buffer: data buffer (in kernel space) + * @len: number of bytes of data to transfer + * + * This will write up to @len bytes of @buffer to the port + * specified, using the IEEE 1284 transfer mode most recently + * negotiated to (using parport_negotiate()), as long as that + * mode supports forward transfers (host to peripheral). + * + * It is the caller's responsibility to ensure that the first + * @len bytes of @buffer are valid. + * + * This function returns the number of bytes transferred (if zero + * or positive), or else an error code. + */ + +ssize_t parport_write (struct parport *port, const void *buffer, size_t len) +{ +#ifndef CONFIG_PARPORT_1284 + return port->ops->compat_write_data (port, buffer, len, 0); +#else + ssize_t retval; + int mode = port->ieee1284.mode; + int addr = mode & IEEE1284_ADDR; + size_t (*fn) (struct parport *, const void *, size_t, int); + + /* Ignore the device-ID-request bit and the address bit. */ + mode &= ~(IEEE1284_DEVICEID | IEEE1284_ADDR); + + /* Use the mode we're in. */ + switch (mode) { + case IEEE1284_MODE_NIBBLE: + case IEEE1284_MODE_BYTE: + parport_negotiate (port, IEEE1284_MODE_COMPAT); + fallthrough; + case IEEE1284_MODE_COMPAT: + pr_debug("%s: Using compatibility mode\n", port->name); + fn = port->ops->compat_write_data; + break; + + case IEEE1284_MODE_EPP: + pr_debug("%s: Using EPP mode\n", port->name); + if (addr) { + fn = port->ops->epp_write_addr; + } else { + fn = port->ops->epp_write_data; + } + break; + case IEEE1284_MODE_EPPSWE: + pr_debug("%s: Using software-emulated EPP mode\n", port->name); + if (addr) { + fn = parport_ieee1284_epp_write_addr; + } else { + fn = parport_ieee1284_epp_write_data; + } + break; + case IEEE1284_MODE_ECP: + case IEEE1284_MODE_ECPRLE: + pr_debug("%s: Using ECP mode\n", port->name); + if (addr) { + fn = port->ops->ecp_write_addr; + } else { + fn = port->ops->ecp_write_data; + } + break; + + case IEEE1284_MODE_ECPSWE: + pr_debug("%s: Using software-emulated ECP mode\n", port->name); + /* The caller has specified that it must be emulated, + * even if we have ECP hardware! */ + if (addr) { + fn = parport_ieee1284_ecp_write_addr; + } else { + fn = parport_ieee1284_ecp_write_data; + } + break; + + default: + pr_debug("%s: Unknown mode 0x%02x\n", + port->name, port->ieee1284.mode); + return -ENOSYS; + } + + retval = (*fn) (port, buffer, len, 0); + pr_debug("%s: wrote %zd/%zu bytes\n", port->name, retval, len); + return retval; +#endif /* IEEE1284 support */ +} + +/** + * parport_read - read a block of data from a parallel port + * @port: port to read from + * @buffer: data buffer (in kernel space) + * @len: number of bytes of data to transfer + * + * This will read up to @len bytes of @buffer to the port + * specified, using the IEEE 1284 transfer mode most recently + * negotiated to (using parport_negotiate()), as long as that + * mode supports reverse transfers (peripheral to host). + * + * It is the caller's responsibility to ensure that the first + * @len bytes of @buffer are available to write to. + * + * This function returns the number of bytes transferred (if zero + * or positive), or else an error code. + */ + +ssize_t parport_read (struct parport *port, void *buffer, size_t len) +{ +#ifndef CONFIG_PARPORT_1284 + pr_err("parport: IEEE1284 not supported in this kernel\n"); + return -ENODEV; +#else + int mode = port->physport->ieee1284.mode; + int addr = mode & IEEE1284_ADDR; + size_t (*fn) (struct parport *, void *, size_t, int); + + /* Ignore the device-ID-request bit and the address bit. */ + mode &= ~(IEEE1284_DEVICEID | IEEE1284_ADDR); + + /* Use the mode we're in. */ + switch (mode) { + case IEEE1284_MODE_COMPAT: + /* if we can tri-state use BYTE mode instead of NIBBLE mode, + * if that fails, revert to NIBBLE mode -- ought to store somewhere + * the device's ability to do BYTE mode reverse transfers, so we don't + * end up needlessly calling negotiate(BYTE) repeately.. (fb) + */ + if ((port->physport->modes & PARPORT_MODE_TRISTATE) && + !parport_negotiate (port, IEEE1284_MODE_BYTE)) { + /* got into BYTE mode OK */ + pr_debug("%s: Using byte mode\n", port->name); + fn = port->ops->byte_read_data; + break; + } + if (parport_negotiate (port, IEEE1284_MODE_NIBBLE)) { + return -EIO; + } + fallthrough; /* to NIBBLE */ + case IEEE1284_MODE_NIBBLE: + pr_debug("%s: Using nibble mode\n", port->name); + fn = port->ops->nibble_read_data; + break; + + case IEEE1284_MODE_BYTE: + pr_debug("%s: Using byte mode\n", port->name); + fn = port->ops->byte_read_data; + break; + + case IEEE1284_MODE_EPP: + pr_debug("%s: Using EPP mode\n", port->name); + if (addr) { + fn = port->ops->epp_read_addr; + } else { + fn = port->ops->epp_read_data; + } + break; + case IEEE1284_MODE_EPPSWE: + pr_debug("%s: Using software-emulated EPP mode\n", port->name); + if (addr) { + fn = parport_ieee1284_epp_read_addr; + } else { + fn = parport_ieee1284_epp_read_data; + } + break; + case IEEE1284_MODE_ECP: + case IEEE1284_MODE_ECPRLE: + pr_debug("%s: Using ECP mode\n", port->name); + fn = port->ops->ecp_read_data; + break; + + case IEEE1284_MODE_ECPSWE: + pr_debug("%s: Using software-emulated ECP mode\n", port->name); + fn = parport_ieee1284_ecp_read_data; + break; + + default: + pr_debug("%s: Unknown mode 0x%02x\n", + port->name, port->physport->ieee1284.mode); + return -ENOSYS; + } + + return (*fn) (port, buffer, len, 0); +#endif /* IEEE1284 support */ +} + +/** + * parport_set_timeout - set the inactivity timeout for a device + * @dev: device on a port + * @inactivity: inactivity timeout (in jiffies) + * + * This sets the inactivity timeout for a particular device on a + * port. This affects functions like parport_wait_peripheral(). + * The special value 0 means not to call schedule() while dealing + * with this device. + * + * The return value is the previous inactivity timeout. + * + * Any callers of parport_wait_event() for this device are woken + * up. + */ + +long parport_set_timeout (struct pardevice *dev, long inactivity) +{ + long int old = dev->timeout; + + dev->timeout = inactivity; + + if (dev->port->physport->cad == dev) + parport_ieee1284_wakeup (dev->port); + + return old; +} + +/* Exported symbols for modules. */ + +EXPORT_SYMBOL(parport_negotiate); +EXPORT_SYMBOL(parport_write); +EXPORT_SYMBOL(parport_read); +EXPORT_SYMBOL(parport_wait_peripheral); +EXPORT_SYMBOL(parport_wait_event); +EXPORT_SYMBOL(parport_set_timeout); +EXPORT_SYMBOL(parport_ieee1284_interrupt); |